\documentclass{article}

\usepackage[french]{babel}
\usepackage[utf8]{inputenc}
\usepackage[lined,boxed,french]{algorithm2e}
\usepackage{graphicx}
\usepackage{amsmath, amssymb}
\usepackage{caption}
\usepackage{subcaption}


\usepackage[top=2.5cm, bottom=2.5cm, left=2cm, right=2cm]{geometry}
\usepackage{fancyhdr}
\lhead{\bsc{Projet Algorithmique Numérique}}
\rhead{\bsc{Résolution d'équations différentielles}}
\renewcommand{\headrulewidth}{1px}
\lfoot{ \bsc{Enseirb-Matmeca}}
\rfoot{ \bsc{Informatique-I1}}
\renewcommand{\footrulewidth}{1px}
\pagestyle{fancy}

%%%%%%%%%%%%%%%% Lengths %%%%%%%%%%%%%%%%
\setlength{\textwidth}{15.5cm}
\setlength{\evensidemargin}{0.5cm}
\setlength{\oddsidemargin}{0.5cm}

%%%%%%%%%%%%%%%% Variables %%%%%%%%%%%%%%%%
\def\projet{6}
\def\titre{Résolution approchée d'équations différentielle\\
						   - - - - - - - - - - - -\\
						  Modélisation de systèmes dynamiques}
\def\team{4}
\def\responsible{jgaleazzi}
\def\secretary{mchatt}
\def\others{bsaintes, gucortes, ekeryelleven}

\begin{document}

%%%%%%%%%%%%%%%% Header %%%%%%%%%%%%%%%%
\noindent\begin{minipage}{\textwidth}
  \vskip 0mm
  \noindent
  { \begin{tabular}{p{7.5cm}}
      {\bfseries \sffamily
        Projet n\degre \projet}
      \begin{center}{\itshape \titre}\end{center}
    \end{tabular}}
  \hfill 
  \fbox{\begin{tabular}{l}
      {~\hfill \bfseries \sffamily Equipe n\degre \team \hfill~} \\[2mm] 
      Responsable : \responsible \\
      Secrétaire  : \secretary \\
      Codeurs     : \others
    \end{tabular}}
  \vskip 4mm ~
  
    ~~~\parbox{0.95\textwidth}{\small \textit{Résumé:}
}
  \vskip 1mm ~
\end{minipage}

% \newpage
\input{differential}
\input{Lotka-Volterra}
\input{pendule}





\end{document}